This invention relates to an improved "insertless" form of automotive cap characterized by removable output distribution electrodes.
Conventional distributor caps have high tension distribution electrodes which are permanently affixed in the cap. The electrodes are metallic circular inserts which are loaded and must be accurately positioned on locator or mold pins in the mold and are subsequently machined to specific dimensions after molding to prevent a flat surface to the distributor rotor electrode.
U.S. Pat. No. 3,789,349 depicts a prior form of "insertless" distributor cap in which the outer electrodes are not molded in and are not permanently affixed in the cap. Each of the outer towers projecting from the domed end of the cap receives a readily removable distributor electrode, one end of which extends into the interior of the cap through slotted opening in the dome thereof in which it is frictionally retained in the cap. The other end of the electrode has a conductive ferrule thereon by which it is attached to one end of a high tension ignition cable, which carries a conventional insulating rubber boot or nipple coaxially surrounding the combined distributor terminal electrode and ignition cable termination.
In addition to simplification of construction and reduction of manufacturing cost afforded by the elimination of locator or positioning pins and the elimination of the necessity to machine the inserts after the molding process, the described form of insertless distributor cap reduces problems of terminal corrosion and loose plug wire connections commonly encountered with conventional distributor caps. However, in closely confined quarters of a crowded engine compartment, insertion of cable attached distributor electrodes into the tower of the distributor cap may be difficult and the electrode may not be properly seated and inserted to a sufficient depth into the interior of the mounted cap for proper cooperation with the distributor input or rotor electrode. Moreover, the frictional retention of the output electrodes in the distributor cap renders the electrodes subject to accidental withdrawal and to displacement or movement by the shock and vibration environment in which the distributor is mounted, resulting in missing and misfiring of the engine.
Accordingly, the present invention has among its objects to provide an improved form of insertless distributor cap and removable output electrode therefor to facilitate blind insertion and alignment of the electrode as well as positive seating and locking thereof within the interior of the cap.
Other objects are to provide an insertless form of distributor cap in which none of the high tension distributor cap electrodes, including the central inner input terminal electrode as well as the outer or output terminal electrodes, is molded in the cap and in which the output terminal electrodes are positively guidingly received and aligned upon insertion of the cap.
Still other objects are to provide a completely insertless form of distributor cap with positive snap-in retention features for the central terminal input electrode and the outer output terminal electrodes.
The above and other objects and advantages of the invention will appear more fully from consideration of the following detailed description of the preferred embodiment of the invention made with reference to the accompanying drawings.